Electromagnetic-suspension and electromagnetic-levitation vehicle systems generally comprise a track having a plurality of substantially continuous rails cooperating with respective magnetic support and guidance units upon the vehicle. Usually a reaction rail on the track cooperates with a linear induction motor on the vehicle to propel the vehicle along the track while the electromagnetic suspension guidance system maintains the vehicle at a given clearance from the track. Other devices associated with the system can include a contact rail cooperating with shoes on the vehicle for delivering electric current to the vehicle or for electrical control and signaling purposes, the track being formed by a plurality of uprights interconnected by a support, e.g. of concrete, along which the various rails are mounted. The vehicle can have support portions which carry the magnet system etc.
Electromagnetic arrangements for the contactless support and guidance of a magnetic levitation vehicle generally include an armature rail which may be of inverted-U section mounted along the track and extending continuously in a longitudinal direction corresponding to the direction of travel of the vehicle. The two shanks of the U are formed with pole surfaces or faces which are spacedly juxtaposed with corresponding pole faces of the core of an electromagnet mounted on the vehicle, this core being likewise of U-section.
The magnetic field between the core and the armature rail, generally by the electrical energization of a coil around the core, provides a magnetic force supporting the vehicle against the downwardly acting force of gravity, the predetermined spacing between the pair of pole faces in the vertical direction being maintained by the corresponding electrical circuitry.
Such systems can include a row of electromagnets on each side of the vehicle for the support and guidance functions.
Conventional magnetic levitation vehicles of the aforedescribed type, for example, the TRANSRAPID system of Krauss-Maffei, Munich, Germany, generally make use of one row of electromagnets on each side of the vehicle to provide the vertical support function and a second row of electromagnets acting independently of the first or in conjunction with the first to provide the desired lateral guide function.
In other words, a magnetic force is generated by virtue of the presence of a second row of electromagnets to counteract centrifugal forces during travel of the vehicle along curves, wind forces and the like acting transversely to the direction of travel.
When two rows of electromagnets are provided on each side of the vehicle to form a combined support and guidance system, the magnets are rigidly connected with the pedestals or undercarriage of the vehicle on which they are mounted.
Customarily, lateral guidance requires energization of the magnet acting in the left-hand and the right-hand directions to different degrees continuously along the travel path of the vehicle.
While this system functions effectively, a problem with it is that the additional row of electromagnets provided on each side of the vehicle to provide the lateral guidance function has considerable mass. When, in an extreme case, the electromagnets of one row are energized maximally and the electromagnets on the other row are energized minimally for a given guidance condition, the supporting force may be found to carry it mostly by only half the number of magnets provided so that at least the more energized side of the electromagnet system may be incapable of carrying the load.